The long-term goal of this project is to apply advances in immunogenetic knowledge to achieve prolongation of organ survival after transplantation. Newer matching techniques that provide information about the HLA-D system will be combined with long-term preservation of kidney allografts. In addition to the classical typing for the HLA-A, B, and C loci antigens and the serological cross-match, we shall use the following approaches. (1) We shall measure HLA-D region compatibility using primed lymphocytes. (a) Lymphocytes of the recipient will be primed to a pool of stimulating cells, and this pool-primed LD typing (pPLT) reagent will be used with cells of potential donors. (b) Primed LD typing (PLT) cells will be used to define the D region antigens on cells of the donor and recipient as the PLT reagents become available. (2) We shall use lymphocytes primed to the cytotoxic target antigens for cytotoxic T lymphocytes in a pool of sensitizing cells to obtain a cellular cross-match for these target antigens. This test, the pool-primed CML (pCML) procedure, will hopefully complement the serological typing for A, B and C locus antigens. These tests will be done prospectively for all kidney allografts. In addition the immunological status of the recipient posttransplantation will be evaluated and monitored with specific attention to changed reactivity to donor LD (in matched leukocyte culture test) and CD (in cell-mediated lympholysis tests) alloantigens. New developments, both with respect to organ preservation and donor-recipient matching, will be added to the protocols as indicated during the grant.